Leaf Margins, Shapes, Bases and Apex- The Wetland Institute

Entire

A smooth leaf margin with no teeth, lobes, or indentations.

Revolute

rolled under, but only at the margin

Aculeate

spiny margined with the teeth long and prickly

Ciliate

Fringed with fine, hair-like structures along the edge.

Serrate

Saw-toothed, featuring sharp teeth that point forward toward the apex (leaf tip).

Double Serrate

Saw-toothed, featuring sharp teeth that point forward toward the apex (leaf tip).

Serrulate

Same as serrate however, finer points (very small)

Crenate

Scalloped or rounded teeth along the margin.

Crenulate

small crenations, or small teeth on rounded protrusions

Sinuate

Having a wavy margin with shallow, rounded indentations.

Dentate

Toothed with symmetrical, outward-pointing sharp teeth.

Denticulate

small dentations

Undulate

wavy in a vertical plane, also called crisped

Lobed/Lobing

Cut or cleft into prominent segments or lobes along the margin. Lobing

The degree to which the blade of a leaf is indented towards the midrib (leaves are only considered lobed if indented more than 1/4 the distance from edge to midrib).

Aristate

Ending in a stiff, bristle-like point.

Acuminate

Tapering gradually to a sharp, protracted point with concave sides.

Cuspidate

Ending in a sharp, rigid point (like a cusp).

Mucronate

Ending abruptly with a short, small spine or point (mucron).

Acute

Tapering to a sharp point with straight or slightly convex sides (forming an angle of less than 90 degrees).

Obtuse

Blunt or rounded at the apex, forming an angle of more than 90 degrees.

Rounded

Curving smoothly in a full semicircle at the tip without a point.

Truncate

Ending abruptly with a flat, square, or abruptly cut-off end.

Retuse

Having a rounded apex with a slight, shallow notch at the center.

Attenuate

Tapering gradually and deeply into a narrow, long point towards the petiole.

Cuneate

Wedge-shaped, tapering evenly to a narrow base.

Oblique or Inequilateral

Asymmetrical; one side of the leaf base is lower or larger than the other.

Cordate

Heart-shaped, featuring a deep notch at the base where it attaches to the stem.

Rounded

Curving smoothly in a broad, convex arc at the base.

Truncate

Appearing as if cut straight across horizontally at the base.

Auriculate

Having small, ear-like lobes projecting downward at the base.

Sagittate

Arrowhead-shaped, with acute basal lobes pointing downward or slightly inward.

Hastate

Spear-shaped, with basal lobes that flare outward horizontally.

Sessile

A leaf attached directly to the stem without a petiole (stalk).

Clasping

The base of the leaf blade wraps partly around or embraces the stem.

Decurrent

The leaf blade tissue extends downward along the stem below the point of attachment.

Perfoliate

The stem appears to pass directly through the middle of the leaf blade.

Connate-Perfoliate

Opposing leaves are fused together around the stem, appearing as a single continuous blade with the stem running through the center.

Peltate

The leaf stalk (petiole) attaches to the underside of the leaf blade rather than at the margin (shield-shaped).